Purpose - This paper traces the evolution of logistics and supply chain management (SCM) and projects the state of the field in the near term with the attendant challenges for those who must plan and ...control logistics supply chain operations.Design methodology approach - Key events that created business logistics are noted, the views of the field leaders are identified and assessed, and research outcomes are compared as a basis for how logistics SCM is viewed today.Findings - The scope of the field has broadened bringing new challenges for researchers and managers, but the broader scope was envisioned from its formation. Improvements in information technology and the just-in-time philosophy are the principal drivers for realizing the potential of boundary-spanning channel management.Research limitations implications - The conclusions and projections are based on the author's interpretation of the events surrounding logistics and the supply chain as they have occurred over the last 45 years.Practical implications - Researchers and managers should find the projections of this paper valuable in defining their action agendas for improving logistics supply chain operations. Principal among the challenges is the need for a boundary-spanning accounting system, for a mechanism of sharing the benefits of cooperation among supply chain members, for enhanced relationship skills of logistics supply chain managers, and for improved methods of estimating the revenue contribution potential of the supply chain.Originality value - The personal observations of the author lend a unique perspective as to how the logistics supply chain has developed and what challenges face researchers and managers if the future potential of the field is to be realized.
Road distances are conveniently estimated from distance functions that frequently must be corrected with a multiplier, referred to as a circuity factor, in order to approximate actual travel ...distances. For various regions of the world, these circuity factors differ due to such factors as road network density, travel obstacles, in hilliness. In this note, the circuity factors resulting from a sampling of road networks for various countries and country regions throughout the world are presented. They are particularly useful in designing logistics networks, routing vehicles, and planning in other geographically based logistics applications.
A reverse logistics problem, motivated by blood distribution of the American Red Cross, is examined where containers in which products are delivered from a central processing point to customers ...(stops) in one period are available for return to the central point in the following period. Any container not picked up in the period following its delivery incurs a penalty cost resulting primarily from operating costs and customer dissatisfaction. The result is a dynamic logistics planning problem where in each delivery period the vehicle dispatcher needs to design a multi-stop vehicle route while determining the container quantities to be picked up at each stop. This research is unique in that route design and pickup strategies are developed simultaneously, where stop volumes are known only probabilistically over a planning horizon. A heuristic procedure is developed for treating the route design-pickup strategy planning problem.
•Heuristic is developed for locating intermediate facilities in a supply chain.•Traditional methods have considered either source or demand points alone.•Two effective lower bounds demonstrate the ...quality of the heuristic.
The problem of locating up to a given number of facilities in continuous Euclidean space that can serve as intermediate transshipment points between multiple stakeholders in a supply chain — suppliers and customers — who are distributed over the same space is considered. The first contribution is in considering the multisource Weber problem (MWP) in the presence of both source points and demand points rather than either alone. The second contribution is that the selection of intermediate facilities for further discrete analysis is based on a quantitative determination rather than a subjective selection process, which is typical of most popular commercial-grade mathematical programming (LP and IP) based location models. While the mathematical programming approach benefits from a degree of richness in features and a sense of computational optimization, one limitation is that the candidate locations to be evaluated must be specified, often without any computational basis for them. Computational experiments on randomly generated problem instances and real case studies indicate that significant gains can be achieved with relatively little effort by expanding the boundary of analysis to include multiple suppliers and multiple customers in the analysis and design of a supply chain network. An alternating location-allocation-type heuristic method is developed that is easy to implement. The third contribution is the development of two different lower bounding procedures that demonstrate the high quality of this obtained heuristic solution.
Many firms experience demand from geographically dispersed customers. This demand is satisfied by
mobile servers that travel to the site of the customer. To achieve this in a cost-effective manner, ...the firm needs to decide where to
locate its service centers, which customer regions to
assign to the centers and the
staffing level at each center so that customers experience a defined level of service at minimum cost. To determine adequate staffing levels, we approximate a service center and the customer regions assigned to it as an
M
/
G
/
s
queueing system. Based on this queueing model, we explore properties of two different staffing level functions. The queueing model is embedded in a large-scale integer program. Using the concept of column generation, we develop an algorithm that can efficiently solve moderate-sized problems.
Supply chain is an emerging term that emphasizes interactions among marketing, logistics, and production. With this term and its application come opportunities associated primarily with managing the ...logistics channel across the legal boundaries of enterprises, such as between firms and their suppliers. In this paper, there is a discussion of the evolution of logistics to see how it is defined and practiced today, with the intent of highlighting the emerging opportunities for channel performance improvement. It is shown that supply chain management has moved us from an
intrafunctional vision of the channel toward an
interfunctional and even
inter-organizational one. Examples are given to illustrate the type of problems that are associated with each of these visions. Focus is given to those problems inherent in managing inter-organizationally, since this is where traditional management tools and techniques are no longer appropriate. The new metrics, informational sharing systems, and allocation-of-benefits procedures needed to operate in the expanded channel are discussed.
Purpose - In logistics strategy, it is now being recognized that revenue generation is as important as cost reduction. Although it has long been known that logistics customer service has a positive ...effect on customer satisfaction, little research has been conducted to determine precisely the degree to which logistics customer service affects sales and generates the revenues for the firm. The purpose of this paper is to identify, categorize, and illustrate methods for estimating revenues associated with various levels of logistics customer service offerings.Design methodology approach - The purpose is achieved through simulation, statistics, and case studies.Findings - When the revenue effects of logistics customer service can be approximated, logistics strategies can be formulated that optimize profits and or return on investment. Otherwise, logistics strategy is in danger of being sub-optimized when logistics customer service levels are treated as planning constraints and costs minimized to meet them.Originality value - The paper sets forth a number of methods by which this sales-service relationship can be generated and the effect of service on sales quantified. This provides an important basis for optimizing logistics strategy.
In this paper, a stochastic vehicle routing problem is considered. In particular, customer demand is assumed to be uncertain, and actual demand is revealed only upon the visit to the customer. ...Instead of adopting the simple recourse action of returning to the depot whenever the vehicle runs out of stock, the points along the route at which restocking is to occur are designed into the route. The restocking points may be before a stockout actually occurs. Two heuristic algorithms are developed to construct both single and multiple routes that minimize total travel cost. The computational results show that the heuristic procedures produce quality solutions and are efficient.
Fang and Qi (Optim. Methods Softw. 18:143–165,
2003
) introduced a new generalized network flow model called manufacturing network flow model for manufacturing process modeling. A key distinguishing ...feature of such models is the assembling of component raw-materials,
in a given proportion
, into an end-product. This assembling operation cannot be modeled using usual generalized networks (which allow gains and losses in flows), or using multi-commodity networks (which allow flows of multiple commodity types on a single arc). The authors developed a network-simplex-based algorithm to solve a minimum cost flow problem formulated on such a generalized network and indicated systems of linear equations that need to be solved during the course of the network-simplex-based solution procedure. In this paper, it is first shown how various steps of the network-simplex-based solution procedure can be performed efficiently using appropriate data structures. Further, it is also shown how the resulting system of linear equations can be solved directly on the generalized network.
Designing a supply chain network provides the basic structure for supply chain operations, where the network is a major element in a firm's competitiveness and a significant area of capital ...investment. With the boundary-spanning scope encouraged by supply chain management, the question is whether existing analyses used for network design are adequate. The general answer is yes, because the number of echelons that the analysis must span is self-limiting to a relative few. However, there remain unresolved issues in network design analysis and in the models used to support the analysis that can enhance its accuracy, appropriateness, and acceptability to practitioners. Issues discussed relate to the development of better models, the treatment of the data needed by them, and the need for comparing the various models for network design. PUBLICATION ABSTRACT
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